The present invention relates to the feed structure of a laminate wiring board which facilitates dense arrangement of large scale integrated (LSI) chips.
Generally, a laminate wiring board has wiring layers thereinside which are connected to numerous input and output pins which are in turn exposed to the outside at one side of the wiring board. A number of LSI chips are mounted on that side of the circuit board which is opposite to the input and output pins. It has been customary to feed power to such LSI chips from signal input and output pins and power supply pins through the internal wiring layers, as disclosed in U.S. Pat. No. 4,612,602 by way of example.
In the above-described type of feed structure of a laminate wiring board, a part of input and output pins is exclusively assigned to the input and output of signals, and the remaining part of them is exclusively assigned to the supply of power. A drawback with such a feed structure is that the electrodes available for signal input and output and those available for power supply are few and, therefore, cannot cope with an increasing demand for dense arrangement of LSI chips.